Aircraft escape slides, slide/rafts, rafts and other inflatables, are inflated by use of a gas released from a pressure bottle. The pressure bottle is equipped with an outlet fitting which includes a valve for controlling release of the gas from the bottle. One type of valve includes a valve plug having a retracted, valve-closing position, and an extended, valve-opening position. A spring acts on the valve plug and biases it endwise outwardly towards its extended position. When the valve plug is in its extended position, pressure gas is released from the bottle out through the fitting and into the inflatable. The fitting includes a releasable lock mechanism which contacts the outer end of the valve plug when the valve plug is in its retracted position and prevents the spring from extending the valve plug. This lock mechanism, until released, physically blocks movement of the valve plug from its retracted position out to its extended position.
One known type of releasable lock mechanism includes an elongated cocking arm that is pivotally connected at one of its ends to the fitting, for pivotal movement between a down position and an up position. When the cocking arm is in its down position, it extends laterally of the valve plug, in physical contact with the outer end of the valve plug. This mechanism also includes an elongated look lever which is pivotally connected at one end for pivot movement between a lock position and a release position. The lock lever includes a second end which is in physical contact with the cocking arm when the lock lever is in its lock position. The contact of the locking lever with the cocking lever prevents the cocking lever from moving upwardly from its down position. The lock lever is moved from its lock position to its release position by use of a release cord which is connected to the lock lever, near its second end. When it is desired to release inflation gas from the pressure bottle, a sharp pull is exerted on the release cord, to move the lock lever from its lock position to its release position. When the lock lever is in its release position, it is out of the path traveled by the cocking arm when the cocking arm moves from its down position to its up position. In the past, the biasing spring acting on the valve plug has been relied upon to move the cocking arm from its down position to its up position. The cocking arm is not spring biased but rather is gravity biased towards its down position. The force of gravity acting on the cocking arm maintains the cocking arm in its down position until it is moved upwardly by an extension of the valve plug. The pull on the release cord is a one shot operation. This is because the connection between the release cord and the lock lever is of a type which allows the release cord to separate from the lock lever at the end of the swing path of the lock lever. In such known release mechanism, the lock lever is spring biased towards its lock position. If the valve plug does not extend immediately, the spring acting on the lock lever can swing the lock lever back into its lock position against the cocking arm before the valve plug moves. It then becomes difficult and time consuming to operate the release mechanism.
It is an object of the present invention to prevent a relocking of the lock mechanism, and instead assure that there will always be a release of the mechanism, and in turn a release of inflation gas from the pressure vessel, in response to the pull on the release cord.